Removal of diclofenac sodium and cefixime from wastewater by polymeric PES mixed-matrix-membranes embedded with MIL101-OH/Chitosan

Regarding the presence of residual active drug compounds in the municipal effluents and the effluents of pharmaceutical factories, the removal of these compounds increases the resistance of microorganisms, and environmental hazards, such as genetic disorders in the aquatic reproduction and possible damage to human health is necessary. In recent years, using the Mixed-Matrix-Membranes (MMMs) for their high removal efficiency was considered. In the present study, polyether sulfone (PES) membranes, and composite membranes with MIL10-OH/Chitosan (CS), were synthesized and characterized. SEM analysis shows that with the addition of MOF modified with CS, the number and size of micropores and porosity increase compared to the PES membrane. By adding 0.05 wt % of MIL101-OH and MIL101-OH/CS to the PES membrane, the pure water flux increased from 5.1 kg/m2 h to 9.2 and 9.9 kg/m2 h. Increased porosity in the membranes led to a decrease in the resistance of flowing water, and ultimately increased the membrane's permeability. Increased membrane hydrophilicity, as well as membrane surface roughness, reduced membrane clogging. By adding MOF with CS to the PES membrane, the flux recovery ratio increased from 45 % to 95 % in terms of the increase of hydrophilic functional groups of membrane. Furthermore, reversible fouling increases and irreversible fouling in MMMs significantly decreased. Diclofenac sodium (DCF) was separated better than cefixime (CFX). Thus, the removal percentage for DCF was 95 % and for CFX drug is 90 %. By comparing the removal percentage, it can be seen that the performance of MMMs with MIL101-OH/CS was better than MMMs with MIL101-OH, and adding CS to MOF and PES membrane improved membrane performance to remove DCF and CFX.